Fuel Fill Issue. Sorry to bring this up again

[Terry]

Hi Guys,

First as you can see I'm a newbie here. I'm from Auckland New Zealand and I have just bought my new (to me) Mustang a 2007 GT. It's a gem. I have waited for this moment most of my life. First problem though...I cant fill it up!! So, first Mustang, first post and now my first apology in bringing up such an old issue. But in my defence, it may be old to this forum but it's a brand new and somewhat surprising issue to me!! Yes, I have looked at many forums and the specific thread on this forum (which I didn't post into in case I got told off for bringing up a dead thread) but the answers seem to be all hit and miss. It's the evap system or its' the fuel tank or its the filler pipes tortuous route to the tank or its the way you hold the nozzle or it's the fuel station pump being too aggressive. One suggested the weather was the cause of this inability to get much more than 3/4 of a tank unless you fuel at the rate of about 10 cents a minute!

The fixes range from replacing the tank, to making a make shift vent from the tank, to completely removing the evap system. One guy even said he fixed his problem by removing the evap solenoid by the engine! Standing on the door sill and shaking that ass works well it seems as does standing on your head and whistling Dixie while filling up. Amongst all that, I'm not sure the real problem was ever really identified. A close winner may have been the guy from the Dubai who identified the different filler necks between the 07 and 08/09. Unfortunately, that line of reasoning was never progressed yet I think it sounded the most promising (next to standing on your head whistling Dixie!).

So after all the years the S197 has been out there, this problem doesn't seem to have been solved. It was with some trepidation that within days of taking possession I had the evap canister and system completely removed. I went through every pipe, every filter and tested every solenoid for function and couldn't fault the system. On older cars like this I think a blocked evap system could certainly be the problem and there are many different car makes that suffer this from time to time but my evap system seemed good and clear and no codes are been thrown.

So i am thinking about the Dubai guys suggestion and buying a 08+ fuel filler pipe from Rock Auto to replace the 07 one.

So after all that here is my question. Can this be done? Has anyone ever done it? Did it solve fuel nozzle shutting off and the slow refuel problem?

Sorry (second time) for the long post.

Cheers

Terry

 

[07gts197]

Interested to know myself, Ive never heard about the 08+ filler necks being different. My 07 only has problems intermittently for some odd reason and Ive never done anything to try to solve the issue. The only real fix Ive seen is where a member on here pulled the vent tube and blew it out with compressed air.

 

[Juice]

I also have trouble intermittently, but it is pretty rare. Maybe one out of 30 fillups I have to pump very slow. Some gas pumps seem worse than others.

 

[datmbn]

I think the problem consists of 2 different issues:
1. Unclear EVAp valve or hoses, quite easy to fix just clean and make sure all valves open, or installing new vent pipe.
2. The filler pipe is more or less an S-bend before it reaches the tank, this works well until the fuel level in the tank becomes higher than
filler pipe connection. When the filler pipe comes under the fuel, the small air bubbles that accompany the fuel can no longer follow
the fuel in to the tank, it forms an air lock in the tube. This can, to a certain extent, be corrected by making sure that the tube gets a shorter pull
(constantly goes down) so that the air can evacuate through the pipe. Fix by loosening the pipe from the tank and cut off 20-40 mm and bend the bracket that holds the pipe.
If you have problem 1 then you can probably fill fuel quite unhindered until it suddenly stops and spits back on you,
Do you have problem 2 you can probably fill well to about 1/2 tank after which it can only be filled very slowly, it Probably
work better to fill with the handle up side down (less air will then follow down in the tube)
mvh Mats

 

[texasvoodu]

I am having the same issue and am going to clean the vent and check the filler tube to make sure it isn't collapsed or kinked

 

[s8v4o]

Holding the nozzle 180 degrees from normal (upside down) works for me.

 

[AndrewNagle]

Holding the nozzle 180 degrees from normal (upside down) works for me.

that is what i do and have no issues with this technique

 

[cpeek96]

Holding the nozzle 180 degrees from normal (upside down) works for me.

This or pulling the nozzle out a bit works for me.

 

[Terry]

Thanks guys for the great responses. Looks like it is still an outstanding issue!! In my case, if I put the nozzle even half way in the filler pipe, fuel will not flow at all. The nozzle just shuts off. So I drag it out to the end of the filler pipe and then I can start to get some fuel in but only very slowly. It matters little which way I hold it and in some offset angle cases it just wont refuel at all. This happens from an almost empty tank but becomes aggravatingly slow and sensitive to shutoff from 3/4's. Given the nature and operation of of the auto shut off fuel nozzle it is reasonable to say that fuel is backing up in the pipe and causing the nozzle to shutoff as it is designed to do. But what is causing the fuel to back up and why doesn't this happen to everyone all of the time?

I think I have eliminated the evap system as the cause of this particular problem if only because I am satisfied there are no blockages in any of the pipes or canister (I have blown compressed air through them) and the solenoids are working as they should. I am not throwing any codes either. That leaves the design of the saddle fuel tank or the filler pipe. From what I can tell, the fuel tank in 07 is no different to the 08/09 yet the latter years don't seem to report the problem as much if at all. We know the 05 model had to have its tank replaced under a TSB but I am assuming that fixed that issue and that tank is now standard through to at least 09 where there are none of the refueling issues. So it is significant then that the only difference is that 08/09 models have a redesigned filler pipe with a built in vent!

This leads me to think that filler pipe in the 07 is generally the cause of this problem and that something is preventing the fuel from flowing freely into the tank with consequent rise of fuel in the pipe if not delivered very very slowly. This is not to say evap problems haven't been the cause in other peoples cases and in fact there are many cases of all makes and models of cars suffering from slow refuels associated with blocked evap systems. But in these cases, the car was reported to always refuel without issue until the sudden onset of slow refueling. Servicing the evap system usually finds clogging and fixes the problem. In contrast, this issue with the 07 seems to have plagued the car from new if previous forum threads are to be believed and no amount of evap system servicing fixes it. In what appears to be a high level of frustration some have even completely replaced solenoids, pipes, canisters and filters in their evap system creating a significant dent in the bank balance but no discernible difference to the refuel rate! Ouch!

So why is fuel remaining in the filler neck to such an extent that it fills the neck up, reaches the nozzle and the triggers the nozzles auto shutoff? The simple answer is that something is blocking or more likely, restricting the flow of fuel into the tank. As Texasvoodu suggested above the first port of call is to inspect the pipe for damage or routing that may be leading to collapse, kinking, crushing, squashing or deformation of the pipe. I have checked this of course and in my case everything is as it should be ie all clean, not leaking, undamaged, routed as designed and solidly attached with the mounting bracket. I haven't checked if something is jammed in the pipe. I mean what if some clown has dropped something in there during a refuel at some time in its life? The pipe is routed upwards at one point almost like an 'S' bend on a sink pipe! So anything dropped in there would probably stay in the pipe if it was heavy enough because it wouldn't be pushed uphill and into the tank by the flow of fuel. I'm not inclined to place much store in this theory since this would be the act of an individual that wouldn't lead to a 'fleet wide' and 'global' refueling issue for the 07 model.

Air and venting seems to be the only other logical cause (and the more likely) to fuel flow restriction that causes fuel to back up and trigger the nozzle off. Having addressed the evap system, I am satsified that the tank is venting properly and I even go so far as to say that the rate of fuel delivery into the tank is so low that tank venting is simply not the problem. So what's happening in that filler pipe?

Well firstly, its a really narrow pipe. That seems like a design error right there unless Ford deliberately wanted the S197 to have a slower filling system. They might have wanted that to protect the evap system from getting swamped at fuel top off. But it seems like they might have overcooked it a bit and had to change out the tanks in the 05 and then the fuel filler pipe in the 08/09 to get it where they originally wanted it. The other issue is the shape of the pipe on the 07. The 'S' bend and uphill path do nothing to encourage flow and can only be seen as restrictive to fuel delivery. I'm guessing most modern fuel delivery systems today throughout the world can easily push more fuel down this pipe than it can accept with its restrictive diameter and its tortuous routing. Couple this with the deliberate aeration of fuel as it is delivered (an emissions requirement I believe as aeration reduces fumes) and we now have a lot of air getting locked in this 'S' bend. I think this why not everyone experiences the issue or like Juice in his post above only experience the problem at some fuel stations. Some older fuel delivery systems are slower and without aeration. The aeration I think is a major impediment to fuel flow in a narrow pipe. Without it, the problem is probably not as prevalent.

Ok, so what we can do about this. Well, if you read this far, you either have a major problem filling your tank or you cant sleep! The first thing I am going to try is the suggestion in datmbn's post above related to the cutting down the size of the filler pipe, to take out the looseness and to hopefully straighten it a little. That should help the fuel flow while 'reducing the bubbles' as datmbn points out. If this fails or does not entirely solve the problem, I think there is nothing to lose by replacing the 07 filler pipe with the 08/09 one but I have no idea if they can be made to fit? Would love to hear from some one who has done this.

Before i going cutting fuel delivery pipes or buying new ones, I'd be really interested if you guys think this is a reasonable approach or if I missing something crucial.

Cheers

Terry

 

[skwerl]

On my Chevy C5500 the issue was a bend in the vent line that was zip tied in place. It created a dip in the line that held fuel like a P trap in your kitchen sink plumbing. Once I cut the zip tie and straightened out the line I had no more issues.

On the Mustangs (and virtually any car built in the last 20 years) you also need to stop pumping and hang up the nozzle when the pump shuts off rather than trying to top it off. Once you get past the thought that the pump HAS TO END ON AN EVEN DOLLAR then it ceases to be an issue. Once you have the issue it's a pain in the ass.

 

[dark steed]

Mine only has done it about 3-4 times in 10 years 175K miles and every time from a specific pump at a local gas station.
Turning the nozzle upside down helped but only slightly


Sent from my iPhone using Tapatalk

 

[07gts197]

Which evap lines did you clean?

 

[Terry]

skwerl. Straightening that pipe sounds like a plan that might have some success. Thks.

dark steed. Do you know or can you recall if the pump that caused the refuel problem was newer? Did it deliver faster? Was it delivering very aerated fuel?

07gts197 I cleaned and checked all these for blockages as well as the the one connecting back to the fule tank and the one going forward to the filter/solenoid near the engine.

 

[07gts197]

How about the one going over the axle?

 

[Terry]

I think that's the one going north to the engine bay. Otherwise it was the one to the fuel tank and that was definitely checked too. Of course I was upside down and back to front during all this so 'over the axle' sort of looks 'under the axle' if you know what I mean! In any case, is your suggestion that despite the checks that some pipe may have been missed and that there is a particular pipe which is a strong candidate for blockage?

Cheers
Terry

 

[07gts197]

Not that I doubt you but there is an open ended one that goes over the axle, thats another one that can be plugged. Otherwise in another thread the op took out all the lines you did and said there was like a little box thing that he could hardly blow through. Thats what fixed his issue. What Im getting at is that its not the ones going to the canister purge valve or engine bay.

 

[Terry]

Ahhh...I see what you mean now. Yes I know the pipe you mean. It is effectively an overflow to outside atmosphere if you like. Pretty sure I checked it but now you have brought it up I will check it again just to be sure since it would be a likely place for wasp or mason bee nests. As to the 'little box thing'. Well, I think I might have read the same post as you and definitely checked that. If you look at the photo you will see that box sitting under the two side by side pipes. That was all disassembled and checked for no blockage or resistance. Like the OP I was rather hoping to find this blocked since that would have solved my problem too!! Alas, no such 'luck'. Thanks for checking me through on this 07gts197. Appreciate it.


View attachment 68396

 

[texasvoodu]

Found this Ford tsb
https://latemodel.cachefly.net/downloads/tsb05-14/tsb05-15-12.pdf

 

[RedGt]

This problem can be fixed,look at the video. Works great.

RedGT

 

[ZGrand]

I didn't unnerstan' a word that feller sed.